Or, you can select (in Calibre) to put the metadata in the front of each e-book. Yeah, you'll have to run a re-conversion (e.g. epub to epub), but this way, all your ebooks will have a synopsis at the front of the book.
I did it and, although it't a bit of a PITA to do all/some of your books, I'd do it again.
See this thread for the exact process (I don't have Calibre with me right now to check the exact wording in Preferences):
https://www.mobileread.com/forums/showthread.php?t=95300
Good luck.